A trilby is a type of hat with a narrow, sloping brim and a creased crown. Similar to a fedora, the trilby's key difference is its shorter, more sharply angled brim, which is typically turned up at the back. Originally a men's hat, it gained popularity in the mid-20th century, particularly in Britain, and is now a popular accessory for both men and women. It is a stylish and versatile hat that can be worn for both formal and casual occasions.